[Feature Request] Custom Preview Commands

[Neurognostic]

Custom Preview Commands

In the preview pane I would like to specify a custom command to output for each file type, possibly overriding the built-in providers. This could be implemented similar to the [open] and [opener] config sections in yazi.toml such as [preview].rules and [previewer].

User configurable previewers should allow any possible preview output, especially text, and would remove the burden of needing to add every edge-case previewer provider to the yazi source.

Handling of external commands that output text could be handled like jq is currently. Though some programs might be blocking and have to finish before they output any lines.

External preview commands for images could either be direct to stdout or need to be written to a cache file first and then the standard image preview behavior could be used. An environment variable such as $IMAGE_CACHE_PATH could be passed to the external command's shell to be used as an argument.

Example Use Cases

• Toggle between image preview and mediainfo or exiftool textual/informational previews.
• Toggle between PDF image preview and pdftotext.
• Pandoc conversions. For example, converting .epub or .docx to markdown and then text preview with syntax highlighting.
• Add .epub, .doc, .docx previewer either as image preview or converted with pandoc to markdown
• Microsoft Excel previews with xls2csv
• Convert fonts to image previews

Related Features

Ability to keybind a menu selection of different [previewer] for the selected file type just like the open --interactive menu for open keybinds.

Having a way to globally toggle between image previewers and text previewers.

[sxyazi]

Very similar to what I had in mind. The file preview will be integrated into Yazi's plugin system, with Yazi itself retaining only two basic types (ASCII escape codes and images).

I had begun to experiment with it, and the theme system is its first step. I am currently building the necessary underlying abstractions around it.

[jcguu95]

I would like this feature as well! Thanks for bringing that up.

[sxyazi]

Done by #401.

Here are some examples of built-in plugins: https://github.com/sxyazi/yazi/tree/main/yazi-plugin/preset/plugins

You can try them out on the latest main branch. I'll soon release API documentation for the preloader and previewer at https://yazi-rs.github.io/

[github-actions]

I'm going to lock this issue because it has been closed for 30 days. ⏳ This helps our maintainers find and focus on the active issues. If you have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.